Inside Health

VITAL SIGNS: PATTERNS

VITAL SIGNS: PATTERNS; Autism Cases Level Off in Britain

By JOHN O'NEIL

Published: July 29, 2003

An English study on autism is the first to report what appears to be a leveling off of the steep rise in new cases, the researchers say.

The study, led by Dr. Brent Taylor of University College London, was published last week in The Archives of Disease in Childhood, the pediatric journal of the British Medical Association. An earlier study by Dr. Taylor had described an ''exponential'' increase in the London metropolitan region among children born from 1979 to 1992.

The new study examined new cases among children born in the next six years and found that the prevalence of autism disorders stayed essentially unchanged after 1992, at 2.6 per 1,000 children, a rate in line with other recent surveys and far higher than estimates from 20 years ago.

Autism interferes with the early development of the brain, undermining many skills, including those that are the building blocks for language and social interaction. Reported cases have risen steeply in many countries, outstripping the resources for treatment and setting off a debate over whether the increase reflects greater awareness and better diagnosis or unknown environmental factors.

Dr. Taylor said the findings were consistent with better detection, noting that the age of diagnosis in children fell steadily in the study. That probably made the increase steeper in earlier years, he said.

But Dr. Eric Fombonne, a professor of child and adolescent psychiatry at McGill University, who had no connection with the study, said that its findings should be interpreted with caution. They did not appear to be consistent with data collected in other settings, which appear to continue to show an increase, he said.